Bump version from 5.6.3 to 5.6.4

Author: bvdmitri

Project.toml

@@ -1,7 +1,7 @@
 name = "ReactiveMP"
 uuid = "a194aa59-28ba-4574-a09c-4a745416d6e3"
 authors = ["Dmitry Bagaev <d.v.bagaev@tue.nl>", "Albert Podusenko <a.podusenko@tue.nl>", "Bart van Erp <b.v.erp@tue.nl>", "Ismail Senoz <i.senoz@tue.nl>"]
-version = "5.6.3"
+version = "5.6.4"
 
 [deps]
 BayesBase = "b4ee3484-f114-42fe-b91c-797d54a0c67e"